NAT

NAT changes the IP address in the header when crossing a router. Local IPs are inside the network, global IPs are outside.

Dynamic NAT Configuration #

1. Define a pool of global addresses to be used for translation.

   ip nat pool [name] [start-ip] [end-ip] {netmask [netmask]} {prefix-length [prefix-length]}

2. Configure a standard access list permitting the addresses that should be translated.

   access-list [id] permit [...]

3. Establish dynamic source translation, specifying the access list and pool defined in prior steps.

   ip nat inside source list [id] pool [name]

4. Identify the inside interface.

   interface [...], ip nat inside

5. Identify the outside interface.

   interface [...], ip nat outside